President Obama has outlined a new vision for the fight against terrorism. His speech at the National Defense University in Washington yesterday covered a lot of ground. Obama spoke about limiting drone strikes, working more with allies and closing the Guantanamo Bay prison. Broadly, the president said the terrorist threat against America has changed, and so the time has come to take a hard look at how the U.S. is fighting it.

PRESIDENT BARACK OBAMA: So America's at a crossroads. We must define the nature and scope of this struggle, or else it will define us.

GREENE: NPR's Dina Temple-Raston brings us more.

DINA TEMPLE-RASTON, BYLINE: The changing terrorist threat more than a decade after 9/11 might be summed up with two numbers: 122 and 12. Three years ago there were 122 drone strikes against al-Qaida or its affiliates in Pakistan. So far this year there have been 12.

To hear administration officials tell it, that's because the terrorist threat has diminished. And the president spent an hour yesterday explaining how the U.S. must move away from a perpetual war against terror.

OBAMA: We must define our effort not as a boundless global war on terror, but rather as a series of persistent, targeted efforts to dismantle specific networks of violent extremists that threaten America.

TEMPLE-RASTON: So if the threat is diminished, the machinery built over a decade to fight it should change too. The president said that the standards for using drones to target terrorists need to be tightened and codified. He signed a set of guidelines this week that will govern the use of drones in countries where the U.S. is not at war - places like Pakistan, Yemen and Somalia. The preference would be to capture terrorists. And before a drone can be used there must be near certainty that no civilians will be killed or injured.

OBAMA: To say a military tactic is legal, or even effective, is not to say it is wise or moral in every instance. For the same progress that gives us the technology to strike half a world away also demands the discipline to constrain that power, or risk abusing it.

TEMPLE-RASTON: The president also floated the idea of additional oversight of the drone program to ensure that strikes adhere to the stricter standards. Among his suggestions: a special national security court. Civil liberties advocates say the new guidelines aren't enough.

Elisa Massimino is with Human Rights First.

ELISA MASSIMINO: I think it's important to actually see the documents and the legal theories that underlie this program.

TEMPLE-RASTON: Even with the new attempt at openness, the documents that provide legal justification for the program are still classified. Massimino said that needs to change.

MASSIMINO: We have been in a situation where we start trying to read tea leaves and piece together not only Americans but the rest of the world on what the scope and legal theory underlying the drone program is.

TEMPLE-RASTON: The president also tackled the difficult issue of Guantanamo Bay prison, saying once again that the time had come to close the facility.

OBAMA: And I know the politics are hard. But history will cast a harsh judgment on this aspect of our fight against terrorism and those of us who fail to end it. Imagine a future - 10 years from now, or 20 years from now - when the United States of America is still holding people who have been charged with no crime on a piece of land that is not part of our country.

TEMPLE-RASTON: The president said he had asked the Department of Defense to designate a site inside the United States to hold trials before military commissions. That suggests some detainees could be moved to the U.S. for trial.

Members of Congress have already howled at that idea. The president also said he would appoint a new senior envoy at the State Department whose sole responsibility would be to find of way to transfer most of the 166 detainees out of Guantanamo.

The president didn't say when that appointment would be made. But he did say that it was time to start closing this chapter of America's history.

OBAMA: This war, like all wars, must end. That's what history advises. That's what our democracy demands.